U.S. patent application number 15/449467 was filed with the patent office on 2018-09-06 for snow vehicle.
The applicant listed for this patent is Polaris Industries Inc.. Invention is credited to Phillip M. Driggars, Allen M. Mangum, Cody L. Telford, Justin R. York.
Application Number | 20180251168 15/449467 |
Document ID | / |
Family ID | 63356864 |
Filed Date | 2018-09-06 |
United States Patent
Application |
20180251168 |
Kind Code |
A1 |
Mangum; Allen M. ; et
al. |
September 6, 2018 |
SNOW VEHICLE
Abstract
A snow vehicle is disclosed comprising a vehicle frame, a
propulsion unit coupled to the frame, and a front ski steered by a
steering mechanism. The snow vehicle has a chain coupling the
sprocket of the propulsion unit and a chain tensioning device to
take up the chain tension. The chain has a chain guide positioned
below a lower run of the chain which directs the chain towards an
upper run of the chain.
Inventors: |
Mangum; Allen M.;
(Sandpoint, ID) ; Telford; Cody L.; (Sandpoint,
ID) ; York; Justin R.; (Cocalalla, ID) ;
Driggars; Phillip M.; (Sandpoint, ID) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Polaris Industries Inc. |
Medina |
MN |
US |
|
|
Family ID: |
63356864 |
Appl. No.: |
15/449467 |
Filed: |
March 3, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B62M 27/02 20130101;
B62M 2027/026 20130101; B62M 2027/027 20130101; B62M 2027/021
20130101; B62D 55/07 20130101; B62K 13/08 20130101; B62M 2027/022
20130101; B62M 2027/025 20130101 |
International
Class: |
B62D 55/04 20060101
B62D055/04; B62M 27/02 20060101 B62M027/02; B62K 13/08 20060101
B62K013/08; B62D 55/07 20060101 B62D055/07 |
Claims
1. A rear suspension for a snow vehicle having a vehicle frame and
a propulsion drive member for driving the belt, the rear
suspension, comprising: a rear suspension frame; a drive belt
coupled to the rear suspension frame; a propulsion driven member
supported by the rear suspension frame; a linear element coupling
the propulsion drive member and the propulsion driven member to
drive the drive belt; a coupler for mounting to the rear suspension
frame and for coupling the rear suspension frame to the vehicle
frame; a fastening assembly for fixing the coupler relative to the
rear suspension frame; and a linear assist member for assisting the
movement of the coupler relative to the rear suspension, whereby
when the coupler is fixed relative to the rear suspension frame,
the propulsion drive member and propulsion driven member are fixed
relative to each other, and when the fastening assembly allows
relative movement of the rear suspension frame and the vehicle
frame, the linear assist member may be activated to move the
propulsion drive member and propulsion driven member relative to
each other, to tighten the linear element.
2. The snow vehicle of claim 1, wherein the linear assist member is
a jackscrew coupled to either the coupler or the rear suspension
frame.
3. The snow vehicle of claim 2, wherein the jackscrew is coupled to
a rear portion of the coupler and moves rearwardly to contact a
portion of the rear suspension frame to effect the linear
movement.
4. The snow vehicle of claim 3, wherein the rear portion of the
coupler is curved inwardly and forwardly to provide a spacing
between the coupler and the rear suspension frame portion.
5. The snow vehicle of claim 3, wherein a lock nut is positioned on
the jackscrew and is movable against the coupler to fix the jack
screw relative to the coupler.
6. The snow vehicle of claim 3, wherein the coupler is forged and
includes a rear wall having a threaded aperture which receives the
jackscrew.
7. The snow vehicle of claim 1, wherein the coupler has a base
portion which is generally rectangular in shape, and a front
portion of the rear suspension frame at least partially encompass
the rectangular base portion.
8. The snow vehicle of claim 7, wherein the front portion comprises
opposing channel portions which receive the rectangular base
portion.
9. The snow vehicle of claim 8, wherein the fastening assembly
comprises at least one fastener extending through the opposing
channel members and the coupler.
10. The rear suspension of claim 9, wherein one of the opposing
channel members or coupler include a slotted aperture through which
the fastener extends.
11. The rear suspension of claim 10, wherein the coupler includes a
front and rear slotted aperture through which front and rear
fasteners extend.
12. The rear suspension of claim 1, wherein the linear element is a
chain and the propulsion driven member is a sprocket.
13. A rear suspension for a snow vehicle having a vehicle frame and
a propulsion drive member for driving the belt, the rear
suspension, comprising: a rear suspension frame having a front
receiving area extending along a generally horizontal plane; a
drive belt coupled to the rear suspension frame; a coupler for
mounting to the rear suspension frame and coupling the rear
suspension frame to the vehicle frame, the coupler having a
generally rectangular body portion which extends in a generally
horizontal plane and which is receivable in the front receiving
area; a fastening assembly for fixing the coupler relative to the
rear suspension frame.
14. The snow vehicle of claim 13, further comprising a propulsion
driven member supported by the rear suspension frame and a linear
element coupling the propulsion drive member and the propulsion
driven member to drive the drive belt.
15. The snow vehicle of claim 14, further comprising a fastening
assembly for fixing the coupler relative to the rear suspension
frame.
16. The snow vehicle of claim 15, further comprising a linear
assist member for assisting the movement of the coupler relative to
the rear suspension, whereby when the coupler is fixed relative to
the rear suspension frame, the propulsion drive member and
propulsion driven member are fixed relative to each other, and when
the fastening assembly allows relative movement of the rear
suspension frame and the vehicle frame, the linear assist member
may be activated to move the propulsion drive member and propulsion
driven member relative to each other, to tighten the linear
element.
17. The snow vehicle of claim 16, wherein the linear assist member
is a jackscrew coupled to either the coupler or the rear suspension
frame.
18. The snow vehicle of claim 17, wherein the jackscrew is coupled
to a rear portion of the coupler and moves rearwardly to contact a
portion of the rear suspension frame to effect the linear
movement.
19. The snow vehicle of claim 18, wherein the rear portion of the
coupler is curved inwardly and forwardly to provide a spacing
between the coupler and the rear suspension frame portion.
20. The snow vehicle of claim 17, wherein a lock nut is positioned
on the jackscrew and is movable against the coupler to fix the jack
screw relative to the coupler.
21. The snow vehicle of claim 17, wherein the coupler is forged and
includes a rear wall having a threaded aperture which receives the
jackscrew.
22. The snow vehicle of claim 13, wherein the front portion of the
rear suspension frame at least partially encompass the rectangular
base portion.
23. The snow vehicle of claim 22, wherein the front portion of the
rear suspension frame comprises opposing channel portions which
receive the rectangular base portion.
24. The snow vehicle of claim 23, wherein the fastening assembly
comprises at least one fastener extending through the opposing
channel members and the coupler.
25. The rear suspension of claim 24, wherein one of the opposing
channel members or coupler include a slotted aperture through which
the fastener extends.
26. The rear suspension of claim 25, wherein the coupler includes a
front and rear slotted aperture through which front and rear
fasteners extend.
27. The rear suspension of claim 13, wherein the linear element is
a chain and the propulsion driven member is a sprocket.
28. A kit for converting a motor bike into a snow bike, where the
motor bike has a bike frame and a propulsion member, the kit
comprising: a rear suspension having a suspension frame and a drive
belt coupled to the rear suspension frame, the drive belt being
coupled to the suspension member and having a belt width; and a
front ski coupled to a steering mechanism of the motor bike, the
front ski having a ski width, wherein the ski width is equal to or
greater than the belt width.
29. The kit of claim 28, wherein the ratio of the ski width to the
belt width is in the range of 1/1 to 1.5/1.
30. A rear suspension for a snow vehicle having a vehicle frame and
a propulsion drive member for driving the belt, the rear
suspension, comprising: a rear suspension frame; a drive belt
coupled to the rear suspension frame; a propulsion driven member
coupled to the belt and drivingly coupled to the propulsion drive
member; a linear element coupling the propulsion drive member and
propulsion driven member; and a guide positioned below a lower run
of the linear element and moving the lower run of the linear
element closer to the upper run of the linear element at the
guide.
31. The rear suspension of claim 30, wherein the linear element is
a chain.
32. The rear suspension of claim 31, wherein the guide is a chain
guide having an arcuate convex surface over which the chain is
guided.
33. The rear suspension of claim 32, wherein the rear suspension
frame includes a front frame portion having side by side spine
portions and the propulsion driven member is coupled to one of the
spine portions.
34. The rear suspension of claim 33, wherein the propulsion driven
member is a sprocket.
35. The rear suspension of claim 33, further comprising outer side
panels flanking the spine portions, wherein center spacers separate
the spine portions, and outer spacers separate the spine portions
and the side panels.
36. The rear suspension of claim 35, wherein the chain extends a
longitudinal axis of the vehicle and is positioned between one of
the side panels and one of the spine portions.
37. The rear suspension of claim 36, wherein the chain guide is
coupled to one of the spacers forward of the sprocket.
38. A rear suspension for a snow vehicle having a vehicle frame and
a propulsion drive member for driving the belt, the rear
suspension, comprising: a rear suspension frame; a drive belt
coupled to the rear suspension frame; a propulsion driven member
supported by the rear suspension frame; a linear element coupling
the propulsion drive member and the propulsion driven member to
drive the drive belt; a brake mechanism coupled to the propulsion
driven member and having a cover substantially surrounding the
brake mechanism.
39. The rear suspension of claim 38, wherein the linear element is
a chain.
40. The rear suspension of claim 39, wherein the rear suspension
frame includes a front frame portion having side by side spine
portions and the propulsion driven member is coupled to one of the
spine portions.
41. The rear suspension of claim 40, wherein the propulsion driven
member is a sprocket.
42. The rear suspension of claim 41, wherein the sprocket is
coupled to one of the spine portions and the brake mechanism is
coupled to an opposite side of the spine portion and is connected
by a shaft extending through the spine portion.
43. The rear suspension of claim 42, wherein the brake mechanism
comprises a brake disc and a brake caliper, and one end of the
shaft is coupled to the brake disc.
44. The rear suspension of claim 43, wherein the cover is a two
piece cover and extends over the brake disc and is coupled to the
spine member.
Description
BACKGROUND
[0001] The present disclosure relates to snow vehicles including
snowmobiles and or snow bikes.
[0002] Many types of vehicles are configured with tracks to drive
in the snow. Regardless of whether the vehicle is a snowmobile or a
wheeled vehicle converted to a tracked vehicle, tracked vehicles
typically include a drive shaft mounted to a suspension system that
supports the endless track. The drive shaft typically includes
drive sprockets that engage the endless track. In the case of snow
bikes, it is common that a motor bike is converted by removing the
front tire and replacing it with a ski, and by removing the rear
tire and replacing it with a rear suspension having a drive belt.
Thus it is advantageous if the transition from the motor bike to
the snow bike is made as easy as possible.
[0003] One such snow vehicle is shown in our U.S. Pat. No.
8,910,738, the subject matter of which is incorporated herein by
reference. This patent discloses a conversion of a motorbike into a
snow vehicle where the motorbike powertrain is utilized to power
the track of the converted snow vehicle. Other such snow bikes are
known from our U.S. patent applications, namely: Publications
2015/0144412; 2015/0259032; 2016/0280331 and application Ser. Nos.
14/935,224; 14/935,265 and 15/165,862; the subject matter of which
are incorporated herein by reference.
SUMMARY
[0004] In a first embodiment, a rear suspension is provided for a
snow vehicle having a vehicle frame and a propulsion drive member
for driving the belt. The rear suspension comprises a rear
suspension frame; a drive belt coupled to the rear suspension
frame; a propulsion driven member supported by the rear suspension
frame; a linear element coupling the propulsion drive member and
the propulsion driven member to drive the drive belt; a coupler for
mounting to the rear suspension frame and for coupling the rear
suspension frame to the vehicle frame; a fastening assembly for
fixing the coupler relative to the rear suspension frame; and a
linear assist member for assisting the movement of the coupler
relative to the rear suspension. When the coupler is fixed relative
to the rear suspension frame, the propulsion drive member and
propulsion driven member are fixed relative to each other, and when
the fastening assembly allows relative movement of the rear
suspension frame and the vehicle frame, the linear assist member
may be activated to move the propulsion drive member and propulsion
driven member relative to each other, to tighten the linear
element.
[0005] In another embodiment, a rear suspension is provided for a
snow vehicle having a vehicle frame and a propulsion drive member
for driving the belt. The rear suspension comprises a rear
suspension frame having a front receiving area extending along a
generally horizontal plane; a drive belt coupled to the rear
suspension frame; a coupler for mounting to the rear suspension
frame and coupling the rear suspension frame to the vehicle frame,
the coupler having a generally rectangular body portion which
extends in a generally horizontal plane and which is receivable in
the front receiving area; a fastening assembly for fixing the
coupler relative to the rear suspension frame.
[0006] In another embodiment, a kit is provided for converting a
motor bike into a snow bike, where the motor bile has a bike frame
and a propulsion member. The kit comprises a rear suspension having
a suspension frame and a drive belt coupled to the rear suspension
frame, the drive belt being coupled to the suspension member and
having a belt width; and a front ski coupled to a steering
mechanism of the motor bike, the front ski having a ski width. The
ski width is equal to or greater than the belt width.
[0007] In yet another embodiment, a rear suspension is provided for
a snow vehicle having a vehicle frame and a propulsion drive member
for driving the belt. The rear suspension comprises a rear
suspension frame; a drive belt coupled to the rear suspension
frame; a propulsion driven member supported by the rear suspension
frame; a linear element coupling the propulsion drive member and
the propulsion driven member to drive the drive belt; and a brake
mechanism coupled to the propulsion driven member and having a
cover substantially surrounding the brake mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The invention will now be described in relation to the
drawing figures where:
[0009] FIG. 1 is a side view of the snow vehicle as disclosed in
the present disclosure;
[0010] FIG. 2 shows a left front perspective view of the rear
suspension;
[0011] FIG. 2A is an enlarged portion of the front frame shown in
FIG. 2;
[0012] FIG. 3 shows a right front perspective view of the rear
suspension;
[0013] FIG. 4 shows a left front underside perspective view of the
rear suspension;
[0014] FIG. 5 shows a right front underside perspective view of the
rear suspension;
[0015] FIG. 6 shows a left hand side view of the rear
suspension;
[0016] FIG. 7 shows a left front perspective view of the rear
suspension;
[0017] FIG. 8 is an enlarged portion of the area denoted in FIG.
7;
[0018] FIG. 9 shows a top view of a narrow track frame;
[0019] FIG. 10 shows a top view of a wide track frame;
[0020] FIG. 11 shows a short spool for use in assembling the narrow
track frame of FIG. 9;
[0021] FIG. 12 shows a long spool for use in assembling the wide
track frame of FIG. 10;
[0022] FIG. 13 shows a top perspective view of the chain tensioning
mechanism;
[0023] FIG. 14 is an enlarged portion of the area denoted in FIG.
13;
[0024] FIG. 15 is a top perspective view of the forged coupler
shown in FIG. 13;
[0025] FIG. 16 is an underside perspective view of the forged
coupler shown in FIG. 13;
[0026] FIG. 17A is a view similar to that shown in FIG. 13, showing
the left spine member exploded away from the forged coupler, with
the forged coupler in a fully retracted position;
[0027] FIG. 17B is a view similar to that shown in FIG. 17A, with
the forged coupler in a fully extended position;
[0028] FIG. 18 is a side view of the shock absorber coupled between
the motor bike frame and rear suspension;
[0029] FIG. 19 is an enlarged front perspective view of the front
of the snow bike showing the chain input drive, chain casing and
belt drive;
[0030] FIG. 20 is a side view of the snow bike showing a front of
the snow bike partially broken away to show the chain drive;
[0031] FIG. 21 shows an enlarged perspective view of the chain
guide without the chain;
[0032] FIG. 22 shows an enlarged perspective view of the chain
guide;
[0033] FIG. 23 shows an enlarged perspective view of the brake
mounted within the frame;
[0034] FIG. 24 shows an enlarged perspective view of the brake
without the outer casing;
[0035] FIG. 25 shows an exploded view of the brake assembly;
[0036] FIG. 26 shows a front left perspective view of a portion of
the drive belt;
[0037] FIG. 27 shows a cross-sectional view through lines 27-27 of
FIG. 26;
[0038] FIG. 28 is a front left perspective view of the front ski;
and
[0039] FIG. 29 is an underside perspective view of the ski of FIG.
28.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0040] With reference first to FIG. 1, a snow vehicle is shown
generally at 2 as comprised of a motorcycle portion 4 having a
propulsion unit 6, which is shown as a two-cylinder motorcycle
engine, a frame 8, an operators seat 10, and a steering assembly 12
which includes a front fork 14. A rear suspension assembly 20 is
shown having an upper frame portion 22, slide rails 24, side panels
26, control arms 28, 30, linear force elements 32 and 34 (shown
diagrammatically in FIG. 6 as shock absorbers) and an endless belt
or drive track 36.
[0041] With reference now to FIGS. 2-6, rear suspension 20 will be
described in greater detail. With reference first to FIG. 2, rear
suspension 20 includes a modular frame portion 40, a front coupler
42, and a chain transfer case 44 which couples track drive 46 to an
input chain drive 48. Rear suspension 20 also includes a linear
assist member or chain tensioning mechanism 50 as further described
herein. Modular frame portion 40 includes side panels 26 which are
defined as left-hand plate portion 52 and right-hand plate portion
54 which extend a substantial length of the modular frame 40. As
shown best in FIG. 2A, center spine portions include a left-hand
spine portion 56 and a right-hand spine portion 58 where spine
portions 56, 58 are spaced apart by a front spacer 60, a middle
spacer 62 and a rear spacer 64. Meanwhile, plate portions 52 and 54
are spaced apart from spine portions 56, 58 by way of a front
spacer 70, middle spacer 72 and rear spacer 74. Spacer 60 and 64
are hourglass-shaped in cross section (See FIG. 17A) having
apertures 80 and 82. Thus, one fastener 84 (FIG. 2A) can be
positioned through the front side of spacer 64 to couple the spine
portions 56 and 58 together, while fasteners 86, 88 and 90 couple
the outer plates 52, 54 to the center spines 56, 58 (FIG. 2A).
[0042] Namely, fastener 86 is positioned through plate portion 52,
through the left-hand side spacer 70, through spine portion 56,
through spacer 60, through right-hand side spacer 70, and through
plate 54 to receive a fastener 92 (FIG. 3). In a like manner,
fastener 88 is positioned through plate portion 52, through
left-hand side spacer 72, through spacer 62, through right-hand
side spacer 72, and through plate portion 54 to receive a fastener
94 (FIG. 3). Finally, fastener 90 can be positioned through plate
portion 52, through left-hand side spacer 74, through spacer 64,
through right-hand side spacer 74, through plate portion 54 to
receive the fastener 96 (FIG. 3). It should be appreciated that the
fasteners 86, 88 and 90 could be elongated bolts whereas fasteners
92, 94 and 96 are nuts which thread on the end of bolts 86, 88 and
90; alternatively all of fasteners 86, 88, 90, 92, 94 and 96 could
be bolts where the spacers 60, 62 and 64 are internally threaded to
receive the aforementioned bolts.
[0043] As shown best in FIGS. 3-5, the rear of upper frame portion
40 includes a rear spacer 100 having fastener 102 (FIG. 4) and
fastener 104 (FIG. 3) to couple plate portions 52, 54 together and
spaced apart by spacer 100. A tunnel portion 110 is defined by a
plate 112 which couples to spacer 100 at a rear portion 114 by way
of fasteners 116. Plate portion 112 includes folded-over side edges
120 (FIG. 5) and 122 (FIG. 4) which couple to plate portions 52, 54
by way of fasteners 130 (FIG. 4) and 132 (FIG. 5).
[0044] With the design of the upper frame portion 40 as described
above, the modular design provides for an easy approach to
accommodate multiple frame widths. With reference to FIGS. 7-11,
spacer 74 is shown in greater detail. As shown, spacer 74 is
somewhat spool-shaped having a center portion 140 and embossed ends
142 having an aperture 143 therethrough. With reference to FIG. 9,
spacer 74 is a narrow spacer such that the width of the upper frame
portion 40 is also narrow. As shown in FIG. 12, an elongate spacer
74' is shown. This yields a wider frame upper portion 40' by
including longer spacers 70', 72' and 74', and an elongate end
portion 100' and tunnel plate portion 112', as shown in FIG.
10.
[0045] With reference now to FIGS. 13-17B, front coupler 42 and
chain tensioning mechanism 50 will be described in greater detail.
With reference first to FIG. 15, front coupler 42 is shown as a
forged coupler including a base portion 150 having side walls 152,
154 and an end wall 156. The base portion 150 has a hollowed out
section 158 defining a through passage way at 160 and hollow well
portions 162. A threaded aperture 164 extends through the rear wall
156 and into the hollow portion 158. Wells 162 include a threaded
aperture at 166 which will be described in greater detail herein.
Side walls 152 and 154 include front slotted apertures 170
therethrough and rear slotted apertures 172. A yoke 180 extends
forwardly from the base portion 150 including two yoke arms 182
having apertures at 184. As shown best in FIG. 13, forged coupler
42 is received in a front end of spine portions 56 and 58 such that
apertures 184 (FIG. 15) project forwardly and provide the coupling
to the frame of the motorbike frame.
[0046] With reference now to FIGS. 13, 14, 17A and 17B, the chain
tensioning mechanism 50 will be described in greater detail. With
reference first to FIG. 17A, a front end of spine portions 56 and
58 is shown, where each front end includes a channel-shaped portion
200 defined by an upper wall portion 202 and a lower wall portion
204 defining a channel 206 therebetween. It should be appreciated
that in FIG. 17A, spine portion 56 is spaced apart from its normal
location, having been removed from spacer 64 to show the clarity of
the forged coupler 42 in the channel-shaped portion of spine
portion 58. Channel-shaped portion 200 further includes an aperture
210 which aligns with aperture 80 in spacer 64 and an aperture 212
which aligns with aperture 82 in spacer 64. Channel-shaped portion
200 further includes a front aperture 214 which generally aligns
with slot 170 and an aperture 216 which generally aligns with slot
172. As shown in FIGS. 13 and 17A, a fastener 220 is positioned
through apertures 214 of spine portions 56, 58 and through slotted
portion 170. In a like manner, fastener 222 extends through
apertures 216 of spine portions 56 and 58 and through slot 172. A
fastener plate 230 is provided having nuts 232 positioned in
spaced-apart manner to align with apertures 214 and 216. As
disclosed, nuts 232 are welded to fastener plate 230. This provides
an easy one-person operation, as only the fasteners 220, 222 (FIG.
17A) require a tool to loosen them.
[0047] Thus, this design allows for simple chain tensioning
adjustment. When fasteners 220 and 222 extend through corresponding
apertures 214 and 216, fastening plate 230 can be positioned
against apertures 214 and 216, and fasteners 220, 222 can be
threadibly received in nuts 232. It should be appreciated from
viewing FIG. 17A that forged coupler 42 is in its rearward-most or
retracted position where a front edge of slot 170 is pushed against
fastener 220 and where a front edge of slot 172 is pushed against
fastener 222. Thus, forged coupler 42 may be held in position
trapped in between the spine portions 56 and 58 and more
particularly, in the channel-shaped portions 200 of each of the
spine portions 56, 58.
[0048] With reference now to FIG. 14, a jack bolt 240 is provided
which is threadibly received in threaded aperture 164 (FIG. 15) and
includes a threaded shank at 242, a head 244 and a lock nut is
provided at 246. It should also be appreciated from FIG. 14, that
end wall 156 is curved thereby providing a spacing between end wall
156 and spacer 64. This allows the head 244 and lock nut 246 to be
positioned between the end wall 156 and spacer 64. Thus, chain
tensioning is provided in a very simple operation by loosening
fasteners 220 and 222 which allow forged coupler 42 to move
relative to spine portions 56, 58. As jack bolt 240 is centrally
located between spine portions 56, 58, retracting jack bolt 240
that is, turning head 244 in a counter-clockwise position, would
cause head 244 to abut spacer 64. Continued turning of head 244 in
a counter clockwise direction moves forged coupler 42 and upper
frame portion 40 relative to each other. Thus, this provides chain
tensioning with the chain drive 48 whereby lock nut 246 can be
moved in a clockwise position tightening the lock nut against end
wall 156 locking the jack bolt 240 in its position. As shown in
FIG. 17B, forged coupler 42 is in its forward-most or extended
position where a rear edge of slot 170 is pulled against fastener
220 and where a rear edge of slot 172 is pulled against fastener
222.
[0049] With reference now to FIGS. 19 and 20 the routing of the
chain drive will be described in greater detail. As shown best in
FIG. 19, spine 56 includes a raised portion 250 which allows
mounting of flange 252 which in turn mounts sprocket 254 thereto.
Sprocket 254 receives power from the motor bike from the output
sprocket 256 (see FIG. 20). As shown best in FIG. 20, a linear
element 260 in the form of a chain is routed around sprocket 254
driven by sprocket 256 and positioned over a top of chain guide
266. As shown best in FIG. 22, chain guide 266 includes a U-shaped
aperture 268 such that chain guide 266 is received over spacer 70.
Chain guide 266 further includes an arcuate surface 270 having a
central rib 272 extending therealong. As shown best in FIGS. 5 and
13, a second chain guide 274 is positioned on the left hand side
yoke arm 182, and has a rib 276 which aligns with rib 272 for
contacting the chain 260. Thus, rib 272 can be positioned
intermediate chain links to guide the chain up and away from the
belt 36 as shown best in FIG. 20. As shown in FIG. 20, chain guide
is positioned on the outside of chain 260 pushing chain 260
upwardly towards the upper length of the chain 260. As shown best
in FIGS. 19 and 23, sprocket 254 drives chain transfer case 44
which in turn drives sprockets 280 through shaft 282. Belt 36 is
entrained around sprockets 280, slide rails 24 (FIG. 19), idler
rolls 284 and idler rollers 286 (FIG. 1).
[0050] As shown best in FIGS. 17A and 18, a shock absorber 300 is
shown having a body portion 302, an upper coupling 304 and a lower
coupling 306. As shown best in FIG. 17A, shock 300 is coupled
within well 162 by way lower coupling 306. Lower coupling 306
includes adjustment linkage 310 having threaded rod 312 and
transverse rod 314. Threaded rod 312 includes a jam nut 315, such
that the length of shock 300 can be adjusted by loosening jam nut
315 and threading rod 312 into or out of the body portion 302. As
best shown in FIG. 17A, transverse rod 314 has apertures 316 which
align with apertures 166, for receiving a fastener such as a bolt
therethrough for retaining the lower coupling 306 within the forged
coupling 42.
[0051] With reference now to FIGS. 23-25, brake assembly 320 will
be described in greater detail. As mentioned before, flange 252 is
mounted to a portion 250 of spine 56 which mounts sprocket 254
thereto. Sprocket 254 is coupled to a shaft 321 (shown in phantom
in FIG. 23) which operates a sprocket (not shown) within transfer
case 44, but is also coupled to a brake disk 322 (FIG. 25) of brake
assembly 320. As shown best in FIG. 25, brake assembly 320 includes
a caliper 324 having posts 326 with threaded apertures 328. Flange
252 includes an outer flange portion 252a and an inner flange
portion 252b where the flange portions 252a, 252b include apertures
252c. Flange portions 252a and 252b also include apertures 252d. A
bearing 340 is positioned between the flanged portions 352a and
352b. Fasteners 342 may be positioned through apertures 252c and
received into threaded posts 326; and fastener 344 may be
positioned through apertures 252d, trapping portion 250 of spine 56
therebetween (FIG. 23). A washer 346 and fastener 348 are
positioned on the backside of spine 56 and couple to faster
344.
[0052] It should be understood that shaft 321 also extends through
flange 252 and into splined portion 350 of brake disc 322. A spacer
352 is positioned between bearing 340 and splined portion 350 and
extends over shaft 321. As shown best in FIG. 24, disk 322 is
positioned in a slot 354 of caliper 324, and disk pads (not shown)
contact disc 322 for braking purposes. As also shown in FIG. 25, a
cover surrounds brake disk 322 and includes a cover portion 360 and
cover portion 362. Cover portion 360 is coupled to cover portion
362 by way of fasteners 368 extending through apertures 370 of
cover portion 360 and into threaded engagement with threaded bosses
372 on cover portion 362. Cover portions 360 and 362 are coupled to
spine 56 by way of spacers 380 (see FIGS. 23 and 25) and fasteners
382 extending through apertures 384 and coupled to threaded bosses
386 (FIG. 25) on the back side of cover 372 to couple to spine
56.
[0053] With reference now to FIGS. 26 and 27, belt 36 will be
described in greater detail. As shown in FIG. 26, belt 36 includes
a belt body portion 400 having outer track lugs 402 and inner lugs
404. As shown best in FIG. 27, the distance between an outer edge
408 of the lugs 402 has a width W.sub.1, and the outer width of
track body 400 has a width W.sub.2. In the embodiment shown,
W.sub.2=11.5'' and W.sub.1=11.25'' although W.sub.2 could be
10.75''. Thus, a ratio of W.sub.1/W.sub.2 has a value of 1.022 and
is in the range of 1.0-1.070.
[0054] With reference now to FIGS. 28 and 29, a front ski assembly
is shown at 450, including a spindle portion 452 couple to a ski
454. Ski 454 is substantially similar to that shown in our U.S.
patent application publication number 2015/0259032, incorporated
herein by reference. As shown, a distance between side edges 460 of
ski 454 is W.sub.3. In the embodiment shown, W.sub.3 is equal to or
greater than W.sub.2 (width of belt as shown in FIG. 27), such that
ski 454 flattens the snow for the track belt 36. In the embodiment
shown, the width of the ski is 11.5''. Thus the ratio
W.sub.3/W.sub.2 is 1 to 1, but the ratio of W.sub.3/W.sub.2 has a
range between 1 to 1 and 1.5 to 1 (11.5''-17.25'' ski), and is
preferably in the range 1 to 1 and 1.3 to 1 (11.5''-14.95'' ski)
and more preferably in the range of 1 to 1 and 1.2 to 1
(11.5''-13.8'' ski).
[0055] As shown in FIGS. 9 and 19, the width of the chain transfer
case 44 is very narrow as compared to other previously known snow
bikes. This prevents the transfer case 44 from dragging through the
snow, causing a drag on the snow bike. As shown in FIG. 9, the
nominal width of the frame 40 is W.sub.4 and the total width of the
rear suspension including the transfer case is W.sub.5. In the
embodiment shown, W.sub.4=12.375'' and W.sub.5=13.8125''. The ratio
of the total width to the frame 40 is W.sub.5/W.sub.4 and in the
embodiment shown is 1.116 and has a range of 1.0-1.25, and is
preferably is in the range 1.10-1.2.
[0056] Also, as the mounting of the sprocket 254 is high in the
frame 40, see FIG. 19, the air box in the motor bike need not be
moved which provides ease of installation. Furthermore, since shock
300 is coupled to the forged coupler 42, rather than to the rear
frame 40, the position and angle of the shock 300 never changes,
even when the chain tensioning device 50 is used.
[0057] While this invention has been described as having an
exemplary design, the present invention may be further modified
within the spirit and scope of this disclosure. This application is
therefore intended to cover any variations, uses, or adaptations of
the invention using its general principles. Further, this
application is intended to cover such departures from the present
disclosure as come within known or customary practice in the art to
which this invention pertains.
* * * * *